The present disclosure relates to three-dimensional (3D) printing. In particular, the present disclosure relates to new materials for 3D printing based on photochromatic compounds.
Fused Deposition Modelling (FDM) is one of the more common modes employed in 3D printing. FDM printers use a thermoplastic filament, which is heated to its melting point and then extruded, layer by layer, to create a three dimensional object. In particular, a thermoplastic material is first extruded into filament, then the filament wire supplies material into a heated nozzle. Molten thermoplastic filament is then extruded from the nozzle and material is disposed in layers. FDM printers use a printing material, which constitutes the finished object, and a support material, which acts as a scaffolding to support the object as it is being printed. It has the benefit of being one of the least expensive and most accessible for 3D printers, especially for industrial prototypes and for the home hobbyist.
The most common printing material for FDM is acrylonitrile butadiene styrene (ABS) which is a thermoplastic and has a glass transition temperature of about 105° C. Another common printing material for FDM is poly-lactic acid (PLA) which is a biodegradable thermoplastic aliphatic polyester derived from renewable resources and has a glass transition temperature 60-65° C. Both ABS and PLA are easily melted and fit into small molds. Although several materials with unique specifications are available, such as PLA and ABS, there is a continuing need for new polymers and polymer combinations to provide a wider selection of specifications and capabilities to address various downstream applications of the resultant printed object. For example, while there are thermochromatic compositions known for use in 3D printing, photochromatic compositions for use in 3D printing are very rare.
Thus, there is a need to provide 3D printing compositions that may provide desirable new properties to the resulting 3D printed object such as the ability to change colors based on light exposure.